"Say that again?" Mr. Coats asked in surprise, as the audience laughed. "Did I hear that?"

Mr Putin, speaking to Russian diplomats from around the world assembled in Moscow, said today the Helsinki summit had been successful.

Trump later said he had misspoken and accused "some people" of hating the fact that he got along with Putin.

Earlier on Thursday, both Trump and Putin blamed forces within the United States on Thursday for marring what they called the success of their first summit, with Trump saying he looked forward to their second meeting.

Trump's public doubting of Russia's responsibility in a joint news conference with Putin on Monday provoked some withering criticism from Democrats and Republicans alike and forced the president to make a rare public admission of error. "But that is the president's prerogative".

"He was too enthusiastic, spent too many hours with Putin and he was rocking and rolling", said Gingrich.

"I accept our intelligence community's conclusion that Russia's meddling in the 2016 election took place", he said, reading from prepared remarks, before adding: "Could be other people also".

He also restated the USA intelligence assessment about Russian meddling and Moscow's "ongoing, pervasive efforts to undermine our democracy". "Well, you're right, I don't know what happened at that meeting", Coats said in response to a question at the Aspen Security Forum in Colorado.

There has been no word from Russian Federation about a second Trump-Putin meeting.

The president campaigned on closer ties with Russian Federation, a goal that had been thwarted during his first year in office. "This was the job I signed up for and that was my responsibility". "Because there is no rule of law, as I said, in Russian Federation. But know that it will to the best extent be unvarnished, non-politicised, and the best our incredible intelligence community can produce'". "What we see every day, against our institutions, against our military, against our financial services, against our criticial infrastructure - stretching from those who have major capabilities of doing this, starting with Russian Federation, including China". He also warned of the need to be "ever-vigilant" and "relentless". That's what would have needed to happen for Putin to cooperate with Mueller's office.

Asked by reporters on Wednesday if Russian Federation was still targeting the United States, Trump shook his head and said, "No". It has remained unclear, however, what the president is seeking to accomplish from his negotiations with his Russian counterpart.

"The most important thing that was made at the press conference [in Helsinki on July 16] was Putin's confession, who admitted that Russian Federation had organized a "referendum" in Crimea". Then-CIA director John Brennan, Clapper, former National Security Agency director Adm. Michael Rogers and then-FBI director James Comey all presented the material, describing information that left them convinced of Putin's role, the report states.